The owner of the Barnett National Bank building on Adams Street announced his plans for it Friday, including becoming the home of the One Spark festival, CoWork Jax and KYN. He also plans 80 apartments.

Pedestrians walk by the old Barnett Bank building on Laura Street Friday, April 4, 2014 in downtown Jacksonville, Florida. A mural of an artist's rendering of the future plans for the building at lower left was recently installed by Harbinger Signs in time for the One Spark festival.

The owner of the Barnett National Bank building on Adams Street announced his plans for it Friday, including becoming the home of the One Spark festival, CoWork Jax and KYN. He also plans 80 apartments.

The vision is of a full innovation center, a place to help budding entrepreneurs bring their ideas to market in the heart of downtown Jacksonville. The owner of the Barnett National Bank on Adams Street unveiled his plans for the 18-story building Friday afternoon: A mixed-used building featuring offices, apartments and college classrooms, but with a significant twist.

“We’re creating a hub for the millennial startup group,” said Steve Atkins, whose SouthEast Holdings a year ago paid $3 million for the tower and the buildings known as the Laura Street Trio.

He already has commitments, including Elton Rivas, who said he’s bringing his own trio of enterprises to the building. Rivas is the co-founder of One Spark, the creative festival that kicks off downtown on Wednesday. But he’s also the co-founder of CoWork Jax and KYN, both geared to help new businesses get started and out on their own.

Rivas said the offices for all three are moving to Barnett, taking up about four floors to create what he called “the epicenter of an entrepreneurial eco-system.”

Rivas said he and Atkins had been discussing the plans for at least a year. And though rumors had been floating around about Atkins’ plans, they’d been kept under wrap.

“Well that’s exciting,” said Tony Allegretti, director of downtown engagement for JAX Chamber and to be executor f the Cultural Council of Greater Jacksonville, when he was told Friday afternoon.

“Anytime we can get a reuse of a historic building, it’s good. And I love the use. The younger kids, the college kids, the more students we have downtown, the better it speaks to our vibrancy.”

Here are the full plans for the building, according to Atkins:

The first two floors will be retail. Floors three through eight will be office space for Rivas’ group and college classrooms. The University of North Florida will conduct classes and other functions there, said Robert Wood, dean of continuing education.

Floors nine through 16 will be 80 apartments, geared toward students, of about 700 square feet each with rents of about $1,000 a month.

The 17th floor will be corporate offices, the 18th a sky lounge and conference center.

Total price tag: $30 million to restore the exterior to its historical beginning and to create the living and working spaces inside. But Atkins said he won’t be asking for any city money. Financing is in place, he said, but didn’t say where it’s coming from. He bought the four buildings with a loan from Stache Investments Corp., headed by Jacksonville Jaguars owner Shad Khan.

Construction will start soon after One Spark ends on April 13, he said, with opening planned for summer 2015.

The building is in the center of One Spark, and the project will be showcased during future festivals. The ground floor will display all the elements planned for the building.

One Spark brought an estimated 130,000 people downtown last year, it’s first. But it’s already taking on new significance. Rivas and his team have been invited to Berlin to put on a One Spark there. That’s planned for September.

CoWork Jax is a place where new entrepreneurs can buy memberships to get work space, mentoring or just to hang out with other business people. Jacksonville University’s Davis College of Business recently got involved, buying memberships for students and planning to teach classes there.

It began two years ago, and Rivas said that about 50 businesses have come in, started and moved on.

KYN is what’s referred to as an accelerator. Businesses get four-month courses how to move to the next level. It began last year with a $1 million investment from Khan.

One Spark, CoWork Jax and KYN were formed with the idea of creating a culture of nurturing people with ideas, Rivas said.

“But instead of being miles away,” Atkins said, “it’s an elevator away.”

Wood said he wasn’t sure how many classes UNF will hold in the building. But he said the College of Computing, Engineering and Construction, the Division of Continuing Education and the Small Business Development Center will all have a presence there.

“I would guess that over the course of a year, we’d train over 500 or 1,000 people downtown,” he said.

Atkins’ group bought the Barnett building along with the Laura Street Trio last April. In September, he announced that a 131-room Courtyard by Marriott will go into the Bisbee Building and Florida Life Building.

A restaurant, he said, will go into the Marble Bank. But none has yet been announced.